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    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>Document</title>
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    <body>
        <input type="text" id="myInput" value="张三" name="name">
        <div id="myDiv"><a href="#">标题</a></div>

        <script>
            


            var value = $("#myInput").val()
            alert(value)

            $("#myInput").val("李四")
            var value1 = $("#myInput").val()
            alert(value1)

            $("#myDiv").html("<p>我是p</p>")
            
        </script>
    </body>
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